Convection enhanced delivery device and system

ABSTRACT

A convection enhanced delivery device comprises a support member and an elongated microcatheter carried by the support member. The microcatheter projects lengthwise away from the support member. The microcatheter includes a catheter lumen extending in a first direction. A fluid conduit carried by the support member. The fluid conduit includes a conduit lumen that extends in a second direction different than the first direction. The conduit lumen is in fluid communication with the catheter lumen. An inlet port and a connecting port are also carried by the support member. The inlet port is in fluid communication with the fluid conduit. The connecting port is separate from the inlet port and is in fluid communication with the fluid conduit. The connecting port is configured to engage an end portion of an external fluid conduit such that the external fluid conduit projects away from the connecting port and from the support member.

RELATED APPLICATION

This application claims priority to U.S. Provisional Patent ApplicationSer. No. 62/026,945 filed Jul. 21, 2014, the entire content of which ishereby incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to a convection enhanced delivery devicethat comprises a microcatheter and a fluid conduit carried by a supportmember and, more particularly, to a convection enhanced delivery devicethat comprises a microcatheter carried by a support member and in fluidcommunication with a fluid conduit embedded in the support member.

BACKGROUND OF THE INVENTION

Convection enhanced delivery (“CED”) of a bioactive agent involvesintroducing a fluid containing the bioactive agent into a patient'stissue under pressure so that the fluid moves through the tissue viabulk flow. Implementing CED generally involves inserting multiplecatheters into the tissue to be treated, such as cerebral tissue. Toreduce the risk of hemorrhage and/or trauma to the tissue and to reducethe risk of backflow (i.e., non-delivery into tissue parenchyma), it isdesirable for the catheters to be microcatheters with small outsidediameters.

SUMMARY OF THE INVENTION

The present invention is directed to a convection enhanced deliverydevice that comprises a microcatheter and a fluid conduit carried by asupport member and, more particularly, to a convection enhanced deliverydevice that comprises a microcatheter carried by a support member and influid communication with a fluid conduit embedded in the support member.

In accordance with an embodiment of the present invention, a convectionenhanced delivery device comprises a support member and an elongatedfirst microcatheter carried by the support member. The firstmicrocatheter has a length and projects lengthwise away from the supportmember such that a proximal end of the first microcatheter is disposedadjacent the support member and an opposite distal end of the firstmicrocatheter is spaced apart from the support member. The firstmicrocatheter includes a first catheter lumen extending in a firstdirection lengthwise of the microcatheter. The convection enhanceddelivery device also comprises a first fluid conduit carried by thesupport member. The first fluid conduit includes a first conduit lumen.The first conduit lumen extends in a second direction different than thefirst direction. The first conduit lumen is in fluid communication withthe first catheter lumen. The convection enhanced delivery devicefurther comprises an inlet port carried by the support member and aconnecting port carried by the support member. The inlet port is influid communication with the first conduit. The connecting port isseparate from the inlet port and is in fluid communication with thefirst conduit. The connecting port is configured to engage an endportion of an external fluid conduit such that the external fluidconduit projects away from the connecting port and from the supportmember.

In accordance with another embodiment of the invention, a kit ofcomponents for a convection enhanced delivery system comprises at leasttwo convection enhanced delivery devices and at least one external fluidconduit for interconnecting the at least two convection enhanceddelivery devices. Each convection enhanced delivery device comprises asupport member and an elongated microcatheter carried by the supportmember. The microcatheter has a length and projects lengthwise away fromthe support member such that a proximal end of the microcatheter isdisposed adjacent the support member and an opposite distal end of themicrocatheter is spaced apart from the support member. The microcatheterincludes a catheter lumen extending in a first direction lengthwise ofthe microcatheter. The convection enhanced delivery device alsocomprises a first fluid conduit carried by the support member. The firstfluid conduit includes a conduit lumen. The conduit lumen extends in asecond direction different than the first direction. The conduit lumenis in fluid communication with the catheter lumen. The convectionenhanced delivery device further comprises an inlet port carried by thesupport member and a connecting port carried by the support member. Theinlet port is in fluid communication with the first conduit. Theconnecting port is separate from the inlet port and is in fluidcommunication with the first conduit. The connecting port is configuredto engage an end portion of an external fluid conduit such that theexternal fluid conduit projects away from the connecting port and fromthe support member.

In accordance with a further embodiment of the invention, a convectionenhanced delivery system comprises an external fluid conduit and firstand second convection enhanced delivery devices. The first convectionenhanced delivery device comprises a first support member and anelongated first microcatheter carried by the first support member. Thefirst microcatheter has a length and projects lengthwise away from thefirst support member such that a proximal end of the first microcatheteris disposed adjacent the first support member and an opposite distal endof the first microcatheter is spaced apart from the first supportmember. The first microcatheter includes a first catheter lumenextending in a first direction lengthwise of the first microcatheter.The first convection enhanced delivery device also comprises a firstfluid conduit carried by the first support member. The first fluidconduit includes a first conduit lumen. The first conduit lumen extendsin a second direction different than the first direction and is in fluidcommunication with the first catheter lumen. The first convectionenhanced delivery device further comprises a first inlet port carried bythe first support member and a first connecting port carried by thefirst support member and separate from the first inlet port. The firstinlet port and the first connecting port are in fluid communication withthe first fluid conduit. The first connecting port is configured toengage a first end portion of the external fluid conduit such that theexternal fluid conduit projects away from the first connecting port andfrom the first support member. The second convection enhanced deliverydevice comprises a second support member and an elongated secondmicrocatheter carried by the second support member. The secondmicrocatheter has a length and projects lengthwise away from the secondsupport member such that a proximal end of the second microcatheter isdisposed adjacent the second support member and an opposite distal endof the second microcatheter is spaced apart from the second supportmember. The second microcatheter includes a second catheter lumenextending in a third direction lengthwise of the second microcatheter.The second convection enhanced delivery device also comprises a secondfluid conduit carried by the second support member. The second fluidconduit includes a second conduit lumen. The second conduit lumenextends in a fourth direction different than the third direction and isin fluid communication with the second catheter lumen. The secondconvection enhanced delivery device further comprises a second inletport carried by the second support member and a second connecting portcarried by the second support member and separate from the second inletport. The second inlet port and the second connecting port are in fluidcommunication with the second fluid conduit. The second connecting portengages a second end portion of the external fluid conduit such that theexternal fluid conduit projects away from the second connecting port andfrom the second support member.

In accordance with yet a further embodiment of the invention, aconvection enhanced delivery system comprises a first convectionenhanced delivery device and a mesh support structure. The firstconvection enhanced delivery device comprises a first support member andan elongated first microcatheter carried by the first support member.The first microcatheter has a length and projects lengthwise away fromthe first support member such that a proximal end of the firstmicrocatheter is disposed adjacent the first support member and anopposite distal end of the first microcatheter is spaced apart from thefirst support member. The first microcatheter includes a first catheterlumen extending in a first direction lengthwise of the firstmicrocatheter. The mesh support structure defines openings through themesh support structure. The mesh support structure is configured anddimensioned to support the first support member of the first convectionenhanced delivery device while permitting the first microcathetercarried by the first support member to extend through at least one ofthe openings defined in the mesh support structure.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other features and advantages of the present inventionwill become apparent to one skilled in the art upon consideration of thefollowing description of the invention and the accompanying drawings, inwhich:

FIG. 1 is a schematic top view of a convection enhanced delivery devicein accordance with the present invention;

FIG. 2 is a perspective view of the convection enhanced delivery deviceof FIG. 1;

FIG. 3 is a schematic top view of a plurality of convection enhanceddelivery devices as shown in FIG. 1, which are interconnected to form aconvection enhanced delivery system in accordance with the presentinvention;

FIG. 4 is a perspective view of a convection enhanced delivery devicemounted on a mesh support structure using a first example embodiment ofan attachment mechanism in accordance with the present invention; and

FIG. 5 is a perspective view of a convection enhanced delivery devicemounted on a mesh support structure using a second example embodiment ofan attachment mechanism in accordance with the present invention.

DETAILED DESCRIPTION

FIGS. 1 and 2 illustrate a convection enhanced delivery device 10, inaccordance with an example of the present invention. The convectionenhanced delivery device 10 includes a platform, substrate or supportmember 12, a plurality of microcatheters 14, a plurality of fluidconduits 16, an inlet port 18, and plurality of connecting ports 20. Themicrocatheters 14, the fluid conduits 16, the inlet port 18, and theconnecting ports 20 are supported by or carried by the support member12. The microcatheters 14, the fluid conduits 16, the inlet port 18, andthe connecting ports 20 are also fluidly connected to or in fluidcommunication with one another.

The substrate or support member 12 supports or carries themicrocatheters 14, the fluid conduits 16, the inlet port 18, and theconnecting ports 20. As illustrated in FIGS. 1 and 2, the support member12 is generally square in shape and has a first major surface 22 and anopposite second major surface 24. The first and second major surfacesextend parallel to one another and are spaced apart from one another bya distance that is the thickness “T” of the support member 12. Thethickness “T” is sufficient to permit the fluid conduits 16 and theconnecting ports 20 to be embedded in the support member 12. The supportmember also has four side surfaces 26. Each side surface 26 extendsalong a different one of the four sides of the support member 12 andalso extends from the first major surface 22 to the second major surface24.

The support member 12 is made of a biocompatible material, such as amedical grade silicone. The support member 12 of FIGS. 1 and 2 and thematerial of which the support member is made are flexible. As used inthis application, “flexible” means that a structure or material, such asthe support member 12 or the material of which the support member ismade, is capable of being flexed, which is to say capable of beingturned, bowed, or twisted without breaking. The flexibility of thesupport member 12 is sufficient to permit a surgeon or other health careprovider to bend the support member so that it both generally conformsto the contour of a patient's tissue (not shown) and also maintains suchconformity after being placed in contact with the patient's tissue. As aresult, the second major surface 24 of the support member 12 may bepositioned in substantially complete surface contact with a patient'stissue so as to help provide a barrier against backflow of fluiddelivered to the patient's tissue by the microcatheters 14. Whenpositioned in “substantially complete surface contact” with a patient'stissue, the second major surface 24 has a degree of surface contact thatis as complete as practical to help provide a barrier against backflowwithout unduly lengthening or otherwise degrading the process ofimplanting the support member in a patient's tissue.

Although the support member 12 is shown with a square shape, the supportmember may have any shape, including, for example, rectangular orcircular. The support member 12 may also be relatively rigid, ratherthan flexible, if the circumstances of its use by a surgeon or otherhealth care provider indicate that a relatively rigid support memberwould be desirable. The thickness “T” of the support member 12 may alsobe larger or smaller than shown in FIGS. 1 and 2 in comparison, forexample, to the diameters of the fluid conduits 16 or of the connectingports 20.

The microcatheters 14 project from the second major surface 24 of thesupport member 12. Each microcatheter 14 is an elongated hollow tube andhas a first end 32 and an opposite second end 34. The longest dimensionof each microcatheter 14 is a length “L” that extends from the first end32 of the microcatheter to the second end 34. The first end 32 of eachmicrocatheter 14 is proximal to the support member 12 and is disposedadjacent the support member 12. More specifically, the first end 32either abuts the second major surface 24 of the support member 12 or isdisposed within the support member. The second end 34 of eachmicrocatheter 14 is distal to the support member 12 and is spaced apartfrom the support member 12 by the length “L” of the microcatheter, tothe extent the microcatheter is not embedded in the support member atthe first end 32. Each microcatheter 14 is attached, connected, securedor coupled to the support member 12 at or adjacent to the first end 32of the microcatheter. Attaching, connecting, securing or coupling eachmicrocatheter 14 to the support member 12 may be accomplished, forexample, by using an adhesive, by embedding the first end 32 of themicrocatheter in the support member, or by joining the microcatheter toanother structure, such as one of the fluid conduits 16, that isattached, connected, secured or coupled to the support member. Themicrocatheters 14 are thus supported or carried by the support member12.

Four microcatheters 14 a, 14 b, 14 c, and 14 d are shown in FIGS. 1 and2 arranged in a square pattern. More or fewer microcatheters 14 may beincluded in the convection enhanced delivery device 10. Themicrocatheters 14 may also be arranged in a pattern other than a square.Each microcatheter 14 has a catheter lumen 36 that extends along acentral longitudinal axis of the microcatheter lengthwise of themicrocatheter. The catheter lumen 36 has length equal to the length “L”of the microcatheter 14. Each microcatheter 14 is formed of abiocompatible material, such as polytetrafluoroethylene (“PTFE”), thatis sufficiently rigid to penetrate a patient's tissue and that is alsosufficiently flexible and resilient to withstand being deflected andthen return to a non-deflected position. As used in this application,“resilient” means that a structure or material, such as a microcatheter14 or material of which the microcatheter is made, is capable ofreturning freely to a previous position, shape or condition, which is tosay capable of recovering its size and shape after deformation. Thesecond end 34 of each microcatheter 14 may be sharpened or pointed tofacilitate inserting the microcatheter into a patient's tissue.

The fluid conduits 16 are hollow tubes supported or carried by thesupport member 12. As shown, the fluid conduits 16 are fully embedded inthe support member 12 such that the external circumferential surfaces ofthe fluid conduits 16 are completely covered by the support member. Thefluid conduits 16 may alternatively be only partially embedded in orcovered by the support member 12. As another alternative, the fluidconduits 16 may simply lie on the first major surface 22 of the supportmember 12 and be secured to the support member by, for example, anadhesive.

Each fluid conduit 16 has a conduit lumen 42 that extends along acentral longitudinal axis of the fluid conduit lengthwise of the fluidconduit. Each of the fluid conduits 16 and each of the conduit lumens 42has a longest dimension or length oriented transverse to or, morespecifically as shown, perpendicular to the length “L” of themicrocatheters 14 a-d. Each of the fluid conduits 16 and each of theconduit lumens 42 thus extends in a direction that is different than thedirection in which the microcatheters 14 a-d extend. Each fluid conduit16 is formed of a flexible biocompatible material, such as a medicalgrade silicone. The flexibility of the fluid conduits 16 is sufficientto permit a surgeon or other health care provider to bend the supportmember 12 in which the fluid conduit embedded so that the support memberboth generally conforms to the contour of a patient's tissue (not shown)and also maintains such conformity after being placed in contact withthe patient's tissue.

In the embodiment of FIG. 1, each of the fluid conduits 16 is a straightlength of tube or tubing. Thus, as illustrated in FIG. 1, there is acentral or first fluid conduit 16 a that extends from a first sidesurface 26 a of the support member 12 to an opposite second side surface26 c. A cross or second fluid conduit 16 b extends from a third sidesurface 26 b of the support member 12 to an opposite fourth side surface26 d. The second fluid conduit 16 b is oriented perpendicular to thefirst fluid conduit 16 a. The second fluid conduit 16 b intersects andis fluidly connected to or in fluid communication with the first fluidconduit 16 a.

Intermediate the first side surface 26 a and the second fluid conduit 16b are two connecting fluid conduits or third and fourth fluid conduits16 c and 16 d that extend from the first fluid conduit 16 a to the firstends 32 of two different microcatheters 14 a and 14 b, respectively. Thethird and fourth fluid conduits 16 c and 16 d are fluidly connected toor in fluid communication with the first fluid conduit 16 a and alsowith the microcatheter 14 a and the microcatheter 14 b, respectively.Intermediate the side surface 26 c and the second fluid conduit 16 b aretwo more connecting fluid conduits or fifth and sixth fluid conduits 16e and 16 f that extend from the first fluid conduit 16 a to the firstends 32 of two different microcatheters 14 c and 14 d, respectively. Thefifth and sixth fluid conduits 16 e and 16 f are fluidly connected to orin fluid communication with the first fluid conduit 16 a and also withthe microcatheter 14 c and the microcatheter 14 d, respectively.

The first fluid conduit 16 a extends through and beyond the first sidesurface 26 a of the support member 12, to the right as viewed in FIG. 1.At the right end 44 of the first fluid conduit 16 a, the inlet port 18is joined to the first fluid conduit. The inlet port 18 is configured toengage an end portion of a first external fluid conduit (not shown inFIGS. 1 and 2) such that the external fluid conduit projects away fromthe inlet port 18 and from the support member 12. An external fluidconduit, such as the first external fluid conduit (not shown), isexternal to and separate from the support member 12, but may or may notbe external to a patient's body or tissue. The inlet port 18 may beconfigured in any convenient manner, such as a Luer lock, that willprovide an easily operable, yet securely retained, connection orengagement with the external fluid conduit to help prevent leakage offluid at the inlet port.

At the opposite left end 46 of the first fluid conduit 16 a, aconnecting port 20 c is joined to the first fluid conduit. As can beseen, the connecting port 20 c is separate from the inlet port 18. Themost distal surface of the connecting port 20 c is disposed at the sidesurface 26 c of the support member 12. The connecting port 20 c ispresented in a direction different than the direction in which themicrocatheters 14 a-d extend. The connecting port 20 c is configured toengage an end portion of a second external fluid conduit (not shown inFIGS. 1 and 2) such that the second external fluid conduit projects awayfrom the connecting port 20 c and from the support member 12. Theconnecting port 20 c may be configured in any convenient manner, such asa Luer lock, that will provide an easily operable, yet securelyretained, connection or engagement with the second external fluidconduit to help prevent leakage of fluid at the port. The ends 44 and 46of the first fluid conduit 16 a may abut the inlet port 18 and theconnecting port 20 c, respectively, as shown, or the first fluid conduitmay extend into the inlet port and the connecting port so that the ends44 and 46 are located inside of or at the outer or distal ends of theinlet port and the connecting port.

At one end 48 of the second fluid conduit 16 b, a connecting port 20 bis joined to the second fluid conduit. As can be seen, the connectingport 20 b is separate from the inlet port 18. The most distal surface ofthe connecting port 20 b is disposed at the side surface 26 b of thesupport member 12. The connecting port 20 b is presented in a directiondifferent than the direction in which the microcatheters 14 a-d extend.The connecting port 20 b is configured to engage an end portion of athird external fluid conduit (not shown in FIGS. 1 and 2) such that thethird external fluid conduit projects away from the connecting port 20 band from the support member 12. The connecting port 20 b may beconfigured in any convenient manner, such as a Luer lock, that willprovide an easily operable, yet securely retained, connection orengagement with the third external fluid conduit to help prevent leakageof fluid at the connecting port.

At the opposite end 50 of the second fluid conduit 16 b, a connectingport 20 d is joined to the second fluid conduit. As can be seen, theconnecting port 20 d is separate from the inlet port 18. The most distalsurface of the connecting port 20 d is disposed at the side surface 26 dof the support member 12. The connecting port 20 d is presented in adirection different than the direction in which the microcatheters 14a-d extend. The connecting port 20 d is configured to engage an endportion of a fourth external fluid conduit (not shown in FIGS. 1 and 2)such that the fourth external fluid conduit projects away from theconnecting port 20 d and from the support member 12. The connecting port20 d may be configured in any convenient manner, such as a Luer lock,that will provide an easily operable, yet securely retained, connectionor engagement with the fourth external fluid conduit to help preventleakage of fluid at the connecting port. The ends 48 and 50 of thesecond fluid conduit 16 b may abut the connecting ports 20 b and 20 d,respectively, as shown, or the second fluid conduit may extend into theconnecting ports so that the ends 48 and 50 are located inside of or atthe outer or distal ends of the connecting ports.

As described above, the convection enhanced delivery device 10 of FIGS.1 and 2 includes a plurality of fluid conduits 16 a and 16 c-f that arefluidly interconnected with or in fluid communication with one anotherand with the microcatheters 14 a-14 d. The convection enhanced deliverydevice 10 thereby provides a network of fluid pathways for delivery of afluid bioactive material, such as a liquid pharmaceutical material, fromthe inlet port 18 to the distal or second ends 34 of the microcatheters14 a-d for therapeutic treatment of a patient's tissue. In the networkof fluid pathways, a discrete individual fluid conduit 16 c, 16 d, 16 e,or 16 f leads to and connects with and delivers fluid to each individualmicrocatheter 14 a, 14 b, 14 c, or 14 d, respectively. In addition, thefluid conduits 16 a and 16 b of the convection enhanced delivery device10 of FIGS. 1 and 2 are fluidly interconnected with or in fluidcommunication with one another and with the connecting ports 20 b-d. Theconvection enhanced delivery device 10 thereby provides a network offluid pathways for delivery of a fluid bioactive material, such as aliquid pharmaceutical material, from the inlet port 18 to the connectingports 20 b-d for delivery or transmission to other devices, such asother convection enhanced delivery devices 10, either via directconnection to such other devices or via external conduits (not shown inFIGS. 1 and 2).

FIG. 3 illustrates an example of a convection enhanced delivery system100 that comprises plural or multiple convection enhanced deliverydevices 10 fluidly connected to or in fluid communication with oneanother. More particularly, as shown, the convection enhanced deliverysystem 100 comprises four convection enhanced delivery devices 110, 210,310, and 410. Each of the convection enhanced delivery devices 110, 210,310, and 410 is identical in shape, dimensions, and construction to eachof other convection enhanced delivery devices and to the convectionenhanced delivery device 10 of FIGS. 1 and 2. Accordingly, features orcomponents of the convection enhanced delivery devices 110, 210, 310,and 410 corresponding to features or components of the convectionenhanced delivery device 10 are identified with corresponding referencenumerals increased by 100, 200, 300 or 400, depending upon whichconvection enhanced delivery device 110, 210, 310, or 410 is beingdescribed. Providing all the convection enhanced delivery devices 110,210, 310, and 410 with same shape, dimensions, and construction willtend to reduce the manufacturing cost of the individual convectionenhanced delivery devices and will also tend to facilitate thecollection and production of a kit of parts or components to supply orprovide to a surgeon or other health care provider. At the same time,however, the individual convection enhanced delivery devices 110, 210,310, and 410 may have (a) support members 12 with different shapes anddimensions, (b) different numbers of microcatheters 14, (c) differentnumbers of connecting ports 20, (d) different numbers, shapes, or flowareas of fluid conduits 16, and/or (e) other differences inconstruction.

As illustrated in FIG. 3, the convection enhanced delivery system 100 isconnected to a fluid source 102, such as a pump. The fluid source 102 isfluidly connected to or in fluid communication with a first externalfluid conduit 104 for delivering or supplying a fluid bioactivematerial, such as a liquid pharmaceutical material, to the firstexternal fluid conduit 104 and thus to the convection enhanced deliverysystem 100. The first external fluid conduit 104 has a central lumen andis formed of a flexible biocompatible material, such as a medical gradesilicone. The flexibility of the first external fluid conduit 104 issufficient to permit a surgeon or other health care provider to bend thefirst external fluid conduit as required to fit into the space availableand also to maintain any bend imparted to the first external fluidconduit by the surgeon or other health care provider. The end of thefirst external fluid conduit 104 closest to the fluid source may have anattached port 103 a, which may be configured in any convenient manner,such as a Luer lock, to provide an easily operable, yet securelyretained, connection or engagement with the fluid source 102 to helpprevent leakage of fluid at the port. The first external fluid conduit104 may, for example, be tunneled subcutaneously from the port 103 a sothat only the port 103 a is readily accessible after the convectionenhanced delivery system 100 is fully implanted in a patient's tissue.

The end portion of the first external fluid conduit 104 opposite theport 103 a is engaged with the inlet port 118 of the first convectionenhanced delivery device 110. The end portion of the first externalfluid conduit 104 engaged with the inlet port 118 may have an attachedport 103 b, which may be configured in any convenient manner, such as aLuer lock, to provide an easily operable, yet securely retained,connection or engagement with the inlet port 118 and thus the firstconvection enhanced delivery device 110 to help prevent leakage of fluidat the inlet port.

The first convection enhanced delivery device 110 includes threeconnecting ports 120 b, 120 c, and 120 d. A second external fluidconduit 106 is engaged with the connecting port 120 c. Like the firstexternal fluid conduit 104, the second external fluid conduit 106 has acentral lumen and is formed of a flexible biocompatible material, suchas a medical grade silicone. The flexibility of the second externalfluid conduit 106 is sufficient to permit a surgeon or other health careprovider to bend the second external fluid conduit as required to fitinto the space available and also to maintain any bend imparted to thesecond external fluid conduit by the surgeon or other health careprovider. The end of the second external fluid conduit 106 closest tothe first convection enhanced delivery device 110 may have an attachedport 105 a, which may be configured in any convenient manner, such as aLuer lock, to provide an easily operable, yet securely retained,connection or engagement with the connecting port 120 c of the firstconvection enhanced delivery device 110 to help prevent leakage of fluidat the port.

The end portion of the second external fluid conduit 106 opposite theport 105 a is engaged with the inlet port 218 of the second convectionenhanced delivery device 210. The end portion of the second externalfluid conduit 106 engaged with the inlet port 218 may have an attachedport 105 b, which may be configured in any convenient manner, such as aLuer lock, to provide an easily operable, yet securely retained,connection or engagement with the inlet port 218 and thus the secondconvection enhanced delivery device 210 to help prevent leakage of fluidat the port. The first convection enhanced delivery device 110 is thusfluidly connected to or in fluid communication with the secondconvection enhanced delivery device 210.

The connecting port 120 b of the first convection enhanced deliverydevice 110 is engaged directly with the inlet port 318 of the thirdconvection enhanced delivery device 310. The first convection enhanceddelivery device 110 is thus fluidly connected to or in fluidcommunication with the third convection enhanced delivery device 310.There is no external fluid conduit connected or coupled between theconnecting port 120 b and the inlet port 318 of the third convectionenhanced delivery device 310.

The connecting port 120 d of the first convection enhanced deliverydevice 110 is blocked or closed with a plug (not shown) so that liquidcannot pass through the connecting port. If desired or required,however, the connecting port 120 d may be engaged directly with theinlet port of another convection enhanced delivery device (not shown) orengaged with an external fluid conduit (not shown).

As described above, the inlet port 218 of the second convection enhanceddelivery device 210 is engaged with the port 105 b on one end portion ofthe second external fluid conduit 106 and is thus fluidly connected toor in fluid communication with the first convection enhanced deliverydevice 110. The second convection enhanced delivery device 210 includesthree connecting ports 220 b, 220 c, and 220 d. Each of the threeconnecting ports 220 b, 220 c, and 220 d of the second convectionenhanced delivery device 210 is blocked or closed with a plug (notshown) so that fluid cannot pass through the connecting port. If desiredor required, however, one or more of the connecting ports 220 b, 220 c,and 220 d may be engaged directly with the inlet port of anotherconvection enhanced delivery device (not shown) or engaged with anexternal fluid conduit (not shown).

As also described above, the inlet port 318 of the third convectionenhanced delivery device 310 is engaged directly with the connectingport 120 b of the first convection enhanced delivery device 110. Thethird convection enhanced delivery device 310 includes three connectingports 320 b, 320 c, and 320 d. Each of the connecting ports 320 b and320 d of the third convection enhanced delivery device 310 is blocked orclosed with a plug (not shown) so that liquid cannot pass through theconnecting port. If desired or required, however, one or more of theconnecting ports 320 b and 320 d may be engaged directly with the inletport of another convection enhanced delivery device (not shown) orengaged with an external fluid conduit (not shown).

A third external fluid conduit 108 is engaged with the connecting port320 c of the third convection enhanced delivery device 310. Like thefirst external fluid conduit 104 and the second external fluid conduit106, the third external fluid conduit 108 has a central lumen and isformed of a flexible biocompatible material, such as a medical gradesilicone. The flexibility of the third external fluid conduit 108 issufficient to permit a surgeon or other health care provider to bend thesecond external fluid conduit as required to fit into the spaceavailable and also to maintain any bend imparted to the second externalfluid conduit by the surgeon or other health care provider. The end ofthe third external fluid conduit 108 closest to the third convectionenhanced delivery device 310 may have an attached port 107 a, which maybe configured in any convenient manner, such as a Luer lock, to providean easily operable, yet securely retained, connection or engagement withthe connecting port 320 c of the third convection enhanced deliverydevice 310 to help prevent leakage of fluid at the port.

The end portion of the third external fluid conduit 108 opposite theport 107 a is engaged with the inlet port 418 of the fourth convectionenhanced delivery device 410. The end portion of the third externalfluid conduit 108 engaged with the inlet port 418 may have an attachedport 107 b, which may be configured in any convenient manner, such as aLuer lock, to provide an easily operable, yet securely retained,connection or engagement with the inlet port 418 and thus the fourthconvection enhanced delivery device 410 to help prevent leakage of fluidat the port. The third convection enhanced delivery device 310 is thusfluidly connected to or in fluid communication with the fourthconvection enhanced delivery device 410.

As described above, the inlet port 418 of the fourth convection enhanceddelivery device 410 is engaged with the port 107 b on one end portion ofthe third external fluid conduit 108 and is thus fluidly connected to orin fluid communication with the third convection enhanced deliverydevice 310. The fourth convection enhanced delivery device 410 includesthree connecting ports 420 b, 420 c, and 420 d. Each of the threeconnecting ports 420 b, 420 c, and 420 d of the fourth convectionenhanced delivery device 410 is blocked or closed with a plug (notshown) so that fluid cannot pass through the connecting port. If desiredor required, however, one or more of the connecting ports 420 b, 420 c,and 420 d may be engaged directly with the inlet port of anotherconvection enhanced delivery device (not shown) or engaged with anexternal fluid conduit (not shown).

As a result of the foregoing construction or assembly of the convectionenhanced delivery system 100, fluid may flow from the fluid source 102,along the central lumen of the first external fluid conduit 104, alongthe conduit lumens of the fluid conduits 116 of the first convectionenhanced delivery device 110, along the catheter lumens of themicrocatheters 114 of the first convection enhanced delivery device, andout of the open distal ends of the microcatheters. Fluid may also flowalong the conduit lumens of the fluid conduits 116, through theconnecting port 120 c, along the central lumen of the second externalfluid conduit 106, along the conduit lumens of the fluid conduits 216 ofthe second convection enhanced delivery device 210, along the catheterlumens of the microcatheters 214 of the second convection enhanceddelivery device, and out of the open distal ends of the microcatheters214. Fluid may further flow along the conduit lumens of the fluidconduits 116, through the connecting port 120 b, along the conduitlumens of the fluid conduits 316 of the third convection enhanceddelivery device 310, along the catheter lumens of the microcatheters 314of the third convection enhanced delivery device, and out of the opendistal ends of the microcatheters 314. Fluid may yet further flow alongthe conduit lumens of the fluid conduits 316, through the connectingport 320 c, along the conduit lumens of the conduits 416 of the fourthconvection enhanced delivery device 410, along the catheter lumens ofthe microcatheters 414 of the fourth convection enhanced deliverydevice, and out of the open distal ends of the microcatheters 414.

In use, when the convection enhanced delivery system 100 is to beinserted into tissue, such as cerebral tissue, of a patient, a surgeonor other health care provider selects a convection enhanced deliverydevice, such as the first convection enhanced delivery device 110, froma kit of component parts (not shown). The kit of parts includes thefirst, second, third, and fourth convection enhanced delivery devices110, 210, 310 and 410 and the first, second, and third external fluidconduits 104, 106, and 108. The kit of parts may also include additionalconvection enhanced delivery devices, additional external fluidconduits, and other devices and components that may be required ordesired to provide a selected treatment for the patient's tissue. Thekit of parts may, for example, include a sufficient number of convectionenhanced delivery devices and external fluid conduits to ensure that thesurgeon or other health care provider will have enough convectionenhanced delivery devices to cover a majority of a wall of a resectioncavity in a patient's brain tissue after removal of a tumor.

In one method of implanting the convection enhanced delivery system 100into a patient's tissue, the surgeon or other health care providerimplants the first convection enhanced delivery device 110 into thepatient's tissue at a desired location by pressing the distal ends ofthe microcatheters 114 into the patient's tissue and generallyconforming the support member 112 to the exposed surface of thepatient's tissue. The surgeon or other health care provider thenimplants each of the second, third, and fourth convection enhanceddelivery devices 210, 310, and 410 into the patient's tissue at desiredlocations by pressing the distal ends of the microcatheters 214, 314,and 414, respectively, into the patient's tissue and generallyconforming the support members 212, 312, and 412, respectively, to theexposed surface of the patient's tissue. Thereafter, the surgeon orother health care provider interconnects the first, second, third, andfourth convection enhanced delivery devices 110, 210, 310, and 410 usingexternal fluid conduits 106 and 108 and also direct connections, asappropriate. In another method of implanting the convection enhanceddelivery system 100 into the patient's tissue, the surgeon or otherhealth care provider may first assemble or construct the entireconvection enhanced delivery system by selecting and interconnecting thefirst, second, third, and fourth convection enhanced delivery devices110, 210, 310, and 410 to fit the area or space to be treated, such as aresection cavity, and then implant the entire convection enhanceddelivery system at one time.

With the first, second, third, and fourth convection enhanced deliverydevices 110, 210, 310, and 410 appropriately positioned in the patient'stissue and fluidly interconnected or in fluid communication with oneanother, therapeutic treatment of the tissue with a bioactive materialcan begin. The surgeon or other health care provider connects theconvection enhanced delivery system 100 to the fluid source 102 usingthe first external fluid conduit 104 for delivering a fluid, such as aliquid pharmaceutical material, to the convection enhanced deliverysystem and thus into a patient's tissue. The fluid is delivered from thefluid source 102 into the central lumen of the first external fluidconduit 104. From the first external fluid conduit 104, the fluidcontaining the bioactive material is delivered through the conduitlumens of the fluid conduits 116, 216, 316, and 416 of the first,second, third, and fourth convection enhanced delivery devices 110, 210,310, and 410 into the catheter lumens of the microcatheters 114, 214,314, and 414. The fluid flows along the catheter lumens of themicrocatheters 114, 214, 314, and 414 until it reaches the open ends ofthe distal end portions of the microcatheters and is thereby introducedinto the patient's tissue. When the patient's treatment is completed,the convection enhanced delivery system 100 may be removed bydisconnecting the first external fluid conduit 104 from the fluid source102 and the first convection enhanced delivery device 110 and thenwithdrawing the microcatheters 114, 214, 314, and 414 of themicrocatheters 114, 214, 314, and 414 from the patient's tissue.

As a matter of convenience, FIG. 3 shows the first, second, third, andfourth convection enhanced delivery devices 110, 210, 310, and 410 asthough the first, second, third, and fourth convection enhanced deliverydevices are all implanted in a single, relatively flat tissue surface.Nonetheless, if the convection enhanced delivery system 100 wereimplanted in, for example, a resection cavity, the first, second, third,and fourth convection enhanced delivery devices 110, 210, 310, and 410would often be implanted in tissue surfaces that have differentorientations relative to one another. In such a situation, themicrocatheters 114, 214, 314, and 414 of the convection enhanceddelivery devices 110, 210, 310, and 410, respectively, would extend indifferent directions.

FIG. 4 illustrates an example of a convection enhanced delivery system500 that comprises one or more convection enhanced delivery devices 510mounted on a mesh scaffold or mesh support structure 530. The meshsupport structure 530 may be fabricated from a biocompatible polymer,such as medical grade silicone, or from a biocompatible metal. The meshsupport structure 530 may be woven, as is shown in FIG. 4, withinterwoven, overlying warp and weft filaments or cross members 532 and534 that define interstices or openings 536 between, for example, fourof the cross members. Alternatively, the mesh support structure 530 maybe fabricated as a non-woven openwork grid in which the cross members532 and 534 all lie in a single, common plane and intersect so as todefine interstices or openings 536 between the cross members. Each ofthe openings 536 extends entirely through the mesh structure 530 from anupper surface of the mesh structure to a lower surface of the meshstructure, as viewed in FIG. 4.

The mesh support structure 530 is flexible so that it may be folded,rolled or otherwise formed into a compact package for insertion into anopening in a patient's tissue, such as a resection cavity. Theflexibility of the mesh support structure 530 also permits the meshsupport structure to be unfolded, unrolled or otherwise unpackaged sothat the mesh support structure can be spread out adjacent an exposedsurface of a patient's tissue and generally conform to the contours ofthe exposed surface of the patient's tissue.

The mesh support structure 530 may also be resilient. If the meshsupport structure 530 is resilient, it will tend to return to itsinitial unfolded, unrolled or unpackaged state when it is notconstrained or held in a folded, rolled or otherwise packaged condition.The mesh support structure 530, if resilient, will have a self-expandingcharacteristic and will tend to conform to the contours of the exposedsurface of the patient's tissue. Such a resilient mesh support structure530 will also tend to remain in an expanded or spread-out condition andwill resist forces tending to bend, fold or otherwise deform the meshsupport structure. The mesh support structure 530 may also includelocking mechanisms (not shown) to hold the mesh support structure in anexpanded or spread-out condition. Such locking mechanisms may be lockedand unlocked or released by the surgeon or other health care provider.

The convection enhanced delivery device 510 shown in FIG. 4 may be theonly convection enhanced delivery device used in the convection enhanceddelivery system 500 or the convection enhanced delivery device 510 maybe one of plural or multiple convection enhanced delivery devicesfluidly connected to or in fluid communication with one another in theconvection enhanced delivery system 500. Except as described hereafter,the convection enhanced delivery device 510 is identical in shape,dimensions, and construction to the convection enhanced delivery devices10, 110, 210, 310, and 410 shown in FIGS. 1 to 3. Like the convectionenhanced delivery devices 10, 110, 210, 310, and 410, however, theconvection enhanced delivery device 510 may include a support member 512having a different shape and/or different dimensions than the supportmembers 12, 112, 212, 312, and 412 of FIGS. 1-3. Similarly, theconvection enhanced delivery device 510 may include a different numberof microcatheters 514 with different dimensions than the microcatheters14, 114, 214, 314, and 414 of the convection enhanced delivery devices10, 110, 210, 310, and 410, respectively. Further, the convectionenhanced delivery device 510 may include different numbers of connectingports 520 and different numbers, shapes, or flow areas of fluid conduits516, and/or other differences in construction than the convectionenhanced delivery devices 10, 110, 210, 310, and 410.

Unlike the convection enhanced delivery devices 10, 110, 210, 310, and410, the convection enhanced delivery device 510 includes attachmentmechanisms 540 for mounting the convection enhanced delivery device 510on the mesh support structure 530. Each attachment mechanism 540 has anL-shape with a first leg 542 and a second leg 544. The first leg 542 ofeach attachment mechanism 540 is secured or bonded, at one end, to thesupport member 512 and extends in a direction away from and generallyperpendicular to the support member 512. The first leg 542 is bothflexible and resilient in order to facilitate engaging the attachmentmechanism 540 with the mesh support structure 530. The second leg 544 ofeach attachment mechanism 540 is secured to a distal end of thecorresponding first leg 542 and extends in a direction away from andgenerally perpendicular to the first leg but generally parallel to thesupport member 512. The second leg 544 is relatively rigid and issecured to the distal end of the first leg 542 so as (a) to maintain agenerally perpendicular orientation with respect to the first leg whenthe first leg is in a non-flexed or non-deflected condition and (b) thusto facilitate engaging the attachment mechanism 540 with the meshsupport structure 530.

The attachment mechanisms 540 are typically arranged in pairs, as isshown in FIG. 4. More particularly, a first attachment mechanism 540 ofeach pair of attachment mechanisms is secured to the support member 512so that its second leg 544 extends in a first direction. A secondattachment mechanism 540 of each pair of attachment mechanisms issecured to the support member 512 so that its second leg 544 extends ina second direction opposite the first direction. The second leg 544 ofthe first attachment mechanism 540 may thus pass under and engage with afirst cross member 534 of the mesh support structure 530, and the secondleg 544 of the second attachment mechanism 540 may similarly pass underand engage with a second cross member 534 that is spaced apart from thefirst cross member by one or more openings 536 in the mesh supportstructure 530.

By securing or bonding the first and second attachment mechanisms 540 tothe support member 512 so that the first legs 542 of the attachmentmechanisms are spaced apart by a predetermined distance corresponding tothe distance between two cross members 534, whether or not the crossmembers are immediately adjacent to or next to one another, theresilience of the first legs 542 will tend to keep the first legs inengagement with the cross members 534. Similarly, the resilience of thefirst legs 542 and the relative rigidity of the second legs 544, as wellas the generally perpendicular orientation between the first and secondlegs of each attachment mechanism 540, will tend to keep the second legsin engagement with the cross members 534. By spacing the second legs 544away from the support member 512 by a predetermined distancecorresponding to the diameter of a cross member 534, the convectionenhanced delivery device 510 will be held on the mesh support structure530 without shifting either laterally or vertically, as viewed in FIG.4, relative to the mesh support structure. Although FIG. 4 shows twoattachment mechanisms 540 engaging two cross members 534, the attachmentmechanisms could alternatively engage two cross members 532. There mayalso be more than one pair of attachment mechanisms 540 secured to theconvection enhanced delivery device 510.

To install the convection enhanced delivery device 510 in the meshsupport structure 530 or to mount the convection enhanced deliverydevice on the mesh support structure, a surgeon or other health careprovider may deflect the first legs 542 of the first and secondattachment mechanisms 540 of a pair of such attachment mechanisms towardone another. Deflecting the first legs 542 toward one another by asufficient distance allows the second legs 544 of the first and secondattachment mechanisms 540 to pass between two cross members 534 so thatthe support member 512 of the convection enhanced delivery device 510may be seated in contact with the mesh support structure 530 and themicrocatheters 514 may be inserted into a patient's tissue.

When the convection enhanced delivery device 510 is appropriatelypositioned relative to the mesh support structure 530, and themicrocatheters 514 are appropriately positioned in the patient's tissue,the surgeon or other health care provider may release the first legs 542of the first and second attachment mechanisms 540 of the pair ofattachment mechanisms from their deflected conditions. The resilience ofthe first legs 542 will cause the first legs to move away from oneanother and toward the cross members 534. Such movement will cause thefirst legs 542 to engage or come into contact with the cross members 534and simultaneously cause the second legs 544 of the attachmentmechanisms 540 to move under, as viewed in FIG. 4, the cross members andto engage or come into contact with the cross members. Further, suchmovement will simultaneously cause the second major surface 524 of thesupport member 512 to engage or come into contact with the cross members534.

The convection enhanced delivery device 510 will then be securely andclosely mounted on or attached to the mesh support structure 530. Themesh support structure 530 will hold the microcatheters 514 in theirdesired positions in the patient's tissue. The mesh support structure530 will be particularly effective in this regard if the mesh supportstructure is resilient so that it tends to remain in an expanded orspread-out condition and resists forces tending to bend, fold orotherwise deform it. The attachment mechanisms 540 may subsequently beintentionally released or detached or disengaged from the mesh supportstructure by a surgeon or other health care provider when desired tomove the convection enhanced delivery device or to remove the convectionenhanced delivery device entirely from the patient. The process ofreleasing or detaching or disengaging the convection enhanced deliverydevice 510 from the mesh support structure 530 again involves deflectingthe first legs 542 of the pair of attachment mechanisms 540 toward oneanother so that the attachment mechanisms move out of contact orengagement with the cross member 534 of the mesh support structure.

FIG. 5 illustrates another example of a convection enhanced deliverysystem 600 that comprises one or more convection enhanced deliverydevices 610 mounted on a mesh scaffold or mesh support structure 630.Like the mesh support structure 530, the mesh support structure 630 maybe fabricated from a biocompatible polymer, such as medical gradesilicone, or from a biocompatible metal. The mesh support structure 630may be woven, as is shown in FIG. 5, with interwoven, overlying warp andweft filaments or cross members 632 and 634 that define interstices oropenings 636 between, for example, four of the cross members.Alternatively, the mesh support structure 630 may be fabricated as anon-woven openwork grid in which the cross members 632 and 634 all liein a single, common plane and intersect so as to define interstices oropenings 636 between the cross members. Each of the openings 636 extendsentirely through the mesh structure 630 from an upper surface of themesh structure to a lower surface of the mesh structure, as viewed inFIG. 5.

The mesh support structure 630 is flexible, like the mesh supportstructure 530, so that it may be folded, rolled or otherwise formed intoa compact package for insertion into an opening in a patient's tissue,such as a resection cavity. The flexibility of the mesh supportstructure 630 also permits the mesh support structure to be unfolded,unrolled or otherwise unpackaged so that the mesh support structure canbe spread out adjacent an exposed surface of a patient's tissue andgenerally conform to the contours of the exposed surface of thepatient's tissue.

The mesh support structure 630 may also be resilient. If the meshsupport structure 630 is resilient, it will tend to return to itsinitial unfolded, unrolled or unpackaged state when it is notconstrained or held in a folded, rolled or otherwise packaged condition.The mesh support structure 630, if resilient, will have a self-expandingcharacteristic and will tend to conform to the contours of the exposedsurface of the patient's tissue. Such a resilient mesh support structure630 will also tend to remain in an expanded or spread-out condition andwill resist forces tending to bend, fold or otherwise deform the meshsupport structure. The mesh support structure 630 may also includelocking mechanisms (not shown) to hold the mesh support structure in anexpanded or spread-out condition. Such locking mechanisms may be lockedand unlocked or released by the surgeon or other health care provider.

The convection enhanced delivery device 610 shown in FIG. 5 may be theonly convection enhanced delivery device used in the convection enhanceddelivery system 600 or the convection enhanced delivery device 610 maybe one of plural or multiple convection enhanced delivery devicesfluidly connected to or in fluid communication with one another in theconvection enhanced delivery system 600. Except as described hereafter,the convection enhanced delivery device 610 is identical in shape,dimensions, and construction to the convection enhanced delivery devices10, 110, 210, 310, 410, and 510 shown in FIGS. 1 to 4. Like theconvection enhanced delivery devices 10, 110, 210, 310, 410, and 510,however, the convection enhanced delivery device 610 may include asupport member 612 having a different shape and/or different dimensionsthan the support members 12, 112, 212, 312, 412, and 512 of FIGS. 1-4.Similarly, the convection enhanced delivery device 610 may include adifferent number of microcatheters 614 with different dimensions thanthe microcatheters 14, 114, 214, 314, 414, and 514 of the convectionenhanced delivery devices 10, 110, 210, 310, 410, and 510, respectively.Further, the convection enhanced delivery device 610 may includedifferent numbers of connecting ports 620 and different numbers, shapes,or flow areas of fluid conduits 616, and/or other differences inconstruction than the convection enhanced delivery devices 10, 110, 210,310, 410, and 510.

Like the convection enhanced delivery device 510, but unlike theconvection enhanced delivery devices 10, 110, 210, 310, and 410, theconvection enhanced delivery device 610 includes attachment mechanisms640 for mounting the convection enhanced delivery device 610 on the meshsupport structure 630. Each attachment mechanism 640 has a V-shape witha first leg 642 and a second leg 644. The first leg 642 of eachattachment mechanism 640 has a distal end 646 and a proximal end 648.The second leg 644 of each attachment mechanism 640 has a distal end 650and a proximal end 652. At a location relatively closer to the distalends 646 and 650 of the first and second legs 642 and 644, respectively,than to the proximal ends 648 and 652, a short, relatively rigid link654 extends between the first and second legs. At one end, the link 654is pivotally connected by a hinge 656 to the first leg 642 of theattachment mechanism 640. At its opposite end, the link 654 is pivotallyconnected by a hinge 658 to the second leg 644 of the attachmentmechanism 640. At a location relatively closer to the proximal ends 648and 652 of the first and second legs 642 and 644, respectively, than tothe distal ends 646 and 650, a coil spring 660 extends between the firstand second legs. The coil spring 660 is formed and is attached the firstand second legs 642 and 644 such that the coil spring biases theproximal ends 648 and 652 of the first and second legs away from oneanother. As a result, the coil spring 660 biases the first and secondlegs 642 and 644 to pivot about the hinges 656 and 658 so that thedistal ends 646 and 650 of the first and second legs engage one anotherand tend to remain in contact with each other. The spring-biased contactbetween the distal ends 646 and 650 of the first and second legs 642 and644 facilitates engaging the attachment mechanism 640 with the meshsupport structure 630.

Each of the attachment mechanisms 640 is mounted on the support member612 adjacent its link 654. More specifically, the link 654 extendsthrough a horizontal passage 662 disposed between and generally parallelto the first and second major surfaces 622 and 624 of the support member612. The ends of the link 654 project into spaced apart verticalpassages 664 and 666, each of which extends from the first major surface622 to the second major surface 624 of the support member. Thehorizontal passage 662 thus connects the vertical passages 664 and 666.The vertical passages 664 and 666 are wider (in a left to rightdirection, as viewed in FIG. 5) adjacent the first major surface 622 andnarrower adjacent the second major surface 624. The vertical passage 664receives the first leg 642 of the attachment mechanism 640. The verticalpassage 666 receives the second leg 644 of the attachment mechanism 640.

The increasing widths of the vertical passages 664 and 666 in a verticaldirection, as viewed in FIG. 5, permit the proximal ends 648 and 652 ofthe first and second legs 642 and 644 to be moved toward and away fromone another to cause movement of the distal ends 646 and 650 away fromand toward one another, respectively. As a result, the proximal ends 648and 652 of the first and second legs 642 and 644 may be pinched or movedtoward each other to spread or move the distal ends 646 and 650 awayfrom each other so that a cross member 634 of the mesh support structure630 may be received between the first and second legs adjacent thespaced apart distal ends. With the cross member 634 between the firstand second legs 642 and 644, the proximal ends 648 and 652 of the firstand second legs can be released so as to be biased apart by the coilspring 660 and so that the distal ends 646 and 650 are biased togetheror toward one another. The cross member 634 is thus captured or securedbetween the first and second legs 642 and 644 of the attachmentmechanism 640.

By appropriately determining and fabricating the length of the link 654between the hinges 656 and 658, the length of the first and second legs642 and 644 between the hinges and the distal ends 646 and 650 of thefirst and second legs, and the diameter or width of the cross member634, the biasing force of the coil spring 660 will tend to keep thefirst and second legs, as well as the second major surface 624 of thesupport member 612, in engagement with the cross members 634. Theconvection enhanced delivery device 610 will thus be held on the meshsupport structure 630 without shifting either laterally or vertically,as viewed in FIG. 5, relative to the mesh support structure. AlthoughFIG. 5 shows two attachment mechanisms 640 engaging two cross members634, the attachment mechanisms could alternatively engage two crossmember 632. There may also be more than two attachment mechanisms 640secured to the convection enhanced delivery device 610. Further,although the distal ends 646 and 650 of the first and second legs 642and 644 are shown as blunt tips, the distal ends and adjacent endportions of the first and second legs may be angled or curved toward oneanother to provide a different and potentially more extensive engagementwith the cross members 634.

To install the convection enhanced delivery device 610 in the meshsupport structure 630 or to mount the convection enhanced deliverydevice on the mesh support structure, a surgeon or other health careprovider may pinch or move the proximal ends 648 and 652 of the firstand second legs 642 and 644 of each attachment mechanism 640 toward oneanother. Pinching or moving the proximal ends 648 and 652 of the firstand second legs 642 and 644 of each attachment mechanism 640 toward oneanother by a sufficient distance allows the distal ends 646 and 650 ofthe first and second legs 642 and 644 of the attachment mechanism 640 topass on opposite sides of a cross members 634 so that the support member612 of the convection enhanced delivery device 610 may be seated incontact with the mesh support structure 630 and the microcatheters 614may be inserted into a patient's tissue.

When the convection enhanced delivery device 610 is appropriatelypositioned relative to the mesh support structure 630, and themicrocatheters 614 are appropriately positioned in the patient's tissue,the surgeon or other health care provider may release the proximal ends648 and 652 of the first and second legs 642 and 644 of each attachmentmechanism 640 from their deflected or pinched together condition. Thebias of the coil spring 660 will cause the distal ends 646 and 650 ofthe first and second legs 642 and 644 of the attachment mechanism 640 tomove toward one another and toward the cross member 634. Such movementwill cause the first and second legs 642 and 644 to engage or come intocontact with the cross member 634 and simultaneously cause the secondmajor surface 624 of the support member 612 to engage or come intocontact with the cross member.

The convection enhanced delivery device 610 will then be securely andclosely mounted on or attached to the mesh support structure 630. Themesh support structure 630 will hold the microcatheters 614 in theirdesired positions in the patient's tissue. The mesh support structure630 will be particularly effective in this regard if the mesh supportstructure is resilient so that it tends to remain in an expanded orspread-out condition and resists forces tending to bend, fold orotherwise deform it. The attachment mechanisms 640 may subsequently beintentionally released or detached or disengaged from the mesh supportstructure by a surgeon or other health care provider when desired tomove the convection enhanced delivery device or to remove the convectionenhanced delivery device entirely from the patient. The process ofreleasing or detaching or disengaging the convection enhanced deliverydevice 610 from the mesh support structure 630 again involves pinchingor moving the proximal ends 648 and 652 of the first and second legs 642and 644 of the attachment mechanism 640 toward one another by asufficient distance to allow the cross member 634 to pass between thedistal ends 646 and 650 of the first and second legs 642 and 644 of theattachment mechanism 640 so that the attachment mechanism moves out ofcontact or engagement with the cross member 634 of the mesh supportstructure.

Although the microcatheters 14, 114, 214, 314, 414, 514, and 614 of theconvection enhanced delivery devices 10, 110, 210, 310, 410, 510, and610, respectively, have been described as being introduced into apatient's tissue and then later removed from the patient's tissue, themicrocatheters and/or the entirety of each convection enhanced deliverydevice may be fabricated of a material or materials that can be absorbedby the tissue, thereby reducing or eliminating the requirementphysically to remove the catheters from the patient's tissue. Inaddition, the microcatheters 14, 114, 214, 314, 414, 514, and 614 may befabricated of an electrically conductive material and electricallyinsulated with a coating or jacket except at the tips of the distal endportions of the microcatheters. The microcatheters 14, 114, 214, 314,414, 514, and 614 could thus function as electrodes, conductingelectrical signals applied to the proximal end portions of theperipheral catheters to the patient's tissue for therapeutic electricalstimulation. Further, while the microcatheters 14, 114, 214, 314, 414,514, and 614 and the fluid conduits 16, 116, 216, 316, 416, 516, and 616have been described above and/or illustrated as tubes having a circularcross-section, the microcatheters and the fluid conduits may be tubes ofany cross-sectional shape. Still further, while the fluid conduits 16,116, 216, 316, 416, 516, and 616 have been described above and/orillustrated as components separate from their corresponding supportmembers 12, 112, 212, 312, 412, 512, and 612, the fluid conduits couldbe formed by being molded into or drilled into the support members.

It will be appreciated that the convection enhanced delivery devices 10,110, 210, 310, 410, 510, and 610 may be used to treat both neoplasticand non-neoplastic disorders. Bioactive materials introduced into apatient's tissue using any of the convection enhanced delivery devices10, 110, 210, 310, 410, 510, and 610 may include, for example,chemotherapeutic materials, viruses, proteins, radiologic materials,growth factors, peptides, and non-radioactive tracer molecules. Theconvection enhanced delivery devices 10, 110, 210, 310, 410, 510, and610 may be used in a variety of patient tissues, including, for example,brain tissue, spinal cord tissue, and tissue of any organ.

From the above description of the invention, those skilled in the artwill perceive improvements, changes and modifications. Suchimprovements, changes, and/or modifications within the skill of the artare intended to be covered by the appended claims.

Having described the invention, the following is claimed:
 1. Aconvection enhanced delivery device comprising: (a) a flexible supportmember; (b) an elongated first microcatheter carried by the supportmember, the first microcatheter having a length and projectinglengthwise away from the support member such that a proximal end of thefirst microcatheter is disposed adjacent the support member and anopposite distal end of the first microcatheter is spaced apart from thesupport member, the first microcatheter including a first catheter lumenextending in a first direction lengthwise of the first microcatheter;(c) a first fluid conduit carried by the support member, the first fluidconduit including a first conduit lumen, the first conduit lumenextending in a second direction different than the first direction, thefirst conduit lumen being in fluid communication with the first catheterlumen; (d) an inlet port carried by the support member, the inlet portbeing in fluid communication with the first fluid conduit such thatfluid supplied to the inlet port is delivered by the inlet port to thefirst fluid conduit, the inlet port being presented outwardly of andaway from the support member in a third direction different than thefirst direction, the inlet port being configured to engage an endportion of a first external fluid conduit such that fluid is supplied tothe inlet port by the first external fluid conduit and such that thefirst external fluid conduit projects away from the inlet port and fromthe support member, the inlet port being disposed adjacent a firstexternal surface of the support member presented outwardly of and awayfrom the support member; and (e) a connecting port carried by thesupport member and separate from the inlet port, the connecting portbeing in fluid communication with the first fluid conduit such thatfluid is delivered by the first fluid conduit to the connecting port,the connecting port being presented outwardly of and away from thesupport member in a fourth direction different than the first direction,the connecting port being configured to engage an end portion of asecond external fluid conduit such that fluid delivered to theconnecting port is delivered by the connecting port to the secondexternal fluid conduit and such that the second external fluid conduitprojects away from the connecting port and from the support member, theconnecting port being disposed at or outwardly beyond a second externalsurface of the support member presented outwardly of and away from thesupport member.
 2. A convection enhanced delivery device according toclaim 1 wherein the first fluid conduit is embedded in the supportmember.
 3. A convection enhanced delivery device according to claim 1wherein the first fluid conduit is formed in the support member.
 4. Aconvection enhanced delivery device according to claim 1 furthercomprising a second fluid conduit carried by the support member, thesecond fluid conduit including a second conduit lumen, the secondconduit lumen extending in a fifth direction different than the firstdirection and the second direction, the second conduit lumen being influid communication with the first conduit lumen.
 5. A convectionenhanced delivery device according to claim 1 further comprising (f) anelongated second microcatheter carried by the support member, the secondmicrocatheter having a length and projecting lengthwise away from thesupport member such that a proximal end of the second microcatheter isdisposed adjacent the support member and an opposite distal end of thesecond microcatheter is spaced apart from the support member, the secondmicrocatheter including a second catheter lumen extending in a fifthdirection lengthwise of the second microcatheter; and (g) a second fluidconduit carried by the support member, the second fluid conduitincluding a second conduit lumen, the second conduit lumen extending ina sixth direction different than the first direction and the seconddirection, the second conduit lumen being in fluid communication withthe second catheter lumen.
 6. A convection enhanced delivery deviceaccording to claim 5 wherein the first conduit lumen is in fluidcommunication with the second conduit lumen.
 7. A convection enhanceddelivery device according to claim 1 wherein the support member includesa tissue contacting surface, the tissue contacting surface beingconfigured to be positioned in substantially complete surface contactwith tissue of a patient.
 8. A kit of components for a convectionenhanced delivery system comprising at least two convection enhanceddelivery devices and at least one external connecting fluid conduit forinterconnecting said at least two convection enhanced delivery devices,each convection enhanced delivery device comprising: (a) a flexiblesupport member; (b) an elongated microcatheter carried by the supportmember, the microcatheter having a length and projecting lengthwise awayfrom the support member such that a proximal end of the microcatheter isdisposed adjacent the support member and an opposite distal end of themicrocatheter is spaced apart from the support member, the microcatheterincluding a catheter lumen extending in a first direction lengthwise ofthe microcatheter; (c) a first fluid conduit carried by the supportmember, the first fluid conduit including a conduit lumen, the conduitlumen extending in a second direction different than the firstdirection, the conduit lumen being in fluid communication with thecatheter lumen; (d) an inlet port carried by the support member, theinlet port being in fluid communication with the first fluid conduitsuch that fluid supplied to the inlet port is delivered by the inletport to the first fluid conduit, the inlet port being presentedoutwardly of and away from the support member in a third directiondifferent than the first direction, the inlet port being configured toengage an end portion of a first external fluid conduit such that fluidis supplied to the inlet port by the first external fluid conduit andsuch that the first external fluid conduit projects away from the inletport and from the support member, the inlet port being disposed adjacenta first external surface of the support member presented outwardly ofand away from the support member; and (e) a connecting port carried bythe support member and separate from the inlet port, the connecting portbeing in fluid communication with the first fluid conduit such thatfluid is delivered by the first fluid conduit to the connecting port,the connecting port being presented outwardly of and away from thesupport member in a fourth direction different than the first direction,the connecting port being configured to engage an end portion of the atleast one external connecting fluid conduit such that fluid delivered tothe connecting port is delivered by the connecting port to the at leastone external connecting fluid conduit and such that the at least oneexternal connecting fluid conduit projects away from the connecting portand from the support member, the connecting port being disposed at oroutwardly beyond a second external surface of the support memberpresented outwardly of and away from the support member.
 9. A kit ofcomponents for a convection enhanced delivery system according to claim8 further comprising a mesh support structure, the mesh supportstructure including cross members extending in transverse directions toone another so as to define openings through the mesh support structure,the mesh support structure being configured and dimensioned to supportthe support member of at least one of the convection enhanced deliverydevices while permitting the microcatheter carried by the support memberto extend through at least one of the openings defined in the meshsupport structure by the cross members.
 10. A kit of componentsaccording to claim 8 wherein the support member of each convectionenhanced delivery device includes a tissue contacting surface, thetissue contacting surface being configured to be positioned insubstantially complete surface contact with tissue of a patient.
 11. Aconvection enhanced delivery system comprising: (a) first, second, andthird external fluid conduits; (b) a first convection enhanced deliverydevice comprising (i) a flexible first support member, (ii) an elongatedfirst microcatheter carried by the first support member, the firstmicrocatheter having a length and projecting lengthwise away from thefirst support member such that a proximal end of the first microcatheteris disposed adjacent the first support member and an opposite distal endof the first microcatheter is spaced apart from the first supportmember, the first microcatheter including a first catheter lumenextending in a first direction lengthwise of the first microcatheter,(iii) a first fluid conduit carried by the first support member, thefirst fluid conduit including a first conduit lumen, the first conduitlumen extending in a second direction different than the firstdirection, the first conduit lumen being in fluid communication with thefirst catheter lumen, (iv) a first inlet port carried by the firstsupport member, the first inlet port being in fluid communication withthe first fluid conduit such that fluid supplied to the first inlet portis delivered by the first inlet port to the first fluid conduit, thefirst inlet port being presented outwardly of and away from the firstsupport member in a third direction different than the first direction,the first inlet port engaging an end portion of the first external fluidconduit such that fluid is supplied to the first inlet port by the firstexternal fluid conduit and such that the first external fluid conduitprojects away from the first inlet port and from the first supportmember, the first inlet port being disposed adjacent a first externalsurface of the first support member presented outwardly of and away fromthe first support member, and (v) a first connecting port carried by thefirst support member and separate from the first inlet port, the firstconnecting port being in fluid communication with the first fluidconduit such that fluid is delivered by the first fluid conduit to thefirst connecting port, the first connecting port being presentedoutwardly of and away from the first support member in a fourthdirection different than the first direction, the first connecting portengaging a first end portion of the second external fluid conduit suchthat fluid delivered to the first connecting port is delivered by thefirst connecting port to the second external fluid conduit and such thatthe second external fluid conduit projects away from the firstconnecting port and from the first support member, the first connectingport being disposed at or outwardly beyond a second external surface ofthe first support member presented outwardly of and away from the firstsupport member; and (c) a second convection enhanced delivery devicecomprising (i) a flexible second support member, (ii) an elongatedsecond microcatheter carried by the second support member, the secondmicrocatheter having a length and projecting lengthwise away from thesecond support member such that a proximal end of the secondmicrocatheter is disposed adjacent the second support member and anopposite distal end of the second microcatheter is spaced apart from thesecond support member, the second microcatheter including a secondcatheter lumen extending in a fifth direction lengthwise of the secondmicrocatheter, (iii) a second fluid conduit carried by the secondsupport member, the second fluid conduit including a second conduitlumen, the second conduit lumen extending in a sixth direction differentthan the fifth direction, the second conduit lumen being in fluidcommunication with the second catheter lumen, (iv) a second inlet portcarried by the second support member, the second inlet port being influid communication with the second fluid conduit such that fluidsupplied to the second inlet port is delivered by the second inlet portto the second fluid conduit, the second inlet port being presentedoutwardly of and away from the second support member in a seventhdirection different than the fifth direction, the second inlet portengaging a second end portion of the second external fluid conduit suchthat fluid is supplied to the second inlet port by the second externalfluid conduit and such that the second external fluid conduit projectsaway from the second inlet port and from the second support member, thesecond inlet port being disposed adjacent a first external surface ofthe second support member presented outwardly of and away from thesecond support member, and (v) a second connecting port carried by thesecond support member and separate from the second inlet port, thesecond connecting port being in fluid communication with the secondfluid conduit such that fluid is delivered by the second fluid conduitto the second connecting port, the second connecting port beingpresented outwardly of and away from the second support member in aneighth direction different than the fifth direction, the secondconnecting port engaging an end portion of the third external fluidconduit such that fluid delivered to the second connecting port isdelivered by the second connecting port to the third external fluidconduit and such that the third external fluid conduit projects awayfrom the second connecting port and from the second support member, thesecond connecting port being disposed at or outwardly beyond a secondexternal surface of the second support member presented outwardly of andaway from the second support member.
 12. A convection enhanced deliverysystem according to claim 11, wherein the first convection enhanceddelivery device further comprises (vi) an elongated third microcathetercarried by the first support member, the third microcatheter having alength and projecting lengthwise away from the first support member suchthat a proximal end of the third microcatheter is disposed adjacent thefirst support member and an opposite distal end of the thirdmicrocatheter is spaced apart from the first support member, the thirdmicrocatheter including a third catheter lumen extending in a ninthdirection lengthwise of the third microcatheter; and (vii) a third fluidconduit carried by the first support member, the third fluid conduitincluding a third conduit lumen, the third conduit lumen extending in atenth direction different than the second direction, the third conduitlumen being in fluid communication with the third catheter lumen.
 13. Aconvection enhanced delivery device according to claim 12 wherein thefirst conduit lumen is in fluid communication with the third conduitlumen.
 14. A convection enhanced delivery system according to claim 11further comprising a mesh support structure, the mesh support structureincluding cross members extending in transverse directions to oneanother so as to define openings through the mesh support structure, themesh support structure being configured and dimensioned to support atleast one of the first and second support members while permitting atleast one of the first microcatheter and the second microcathetercarried by said at least one of the first and second support member toextend through at least one of the openings defined in the mesh supportstructure by the cross members.
 15. A convection enhanced deliverysystem according to claim 14, wherein at least one of the first andsecond convection enhanced delivery devices also comprises an attachmentmechanism configured to attach said at least one of the first and secondconvection enhanced delivery devices to the mesh support structure, theattachment mechanism including at least one leg configured anddimensioned to directly engage at least one cross member of the meshsupport structure.
 16. A convection enhanced delivery system accordingto claim 11 wherein each of the first and second support membersincludes a tissue contacting surface, the tissue contacting surfacebeing configured to be positioned in substantially complete surfacecontact with tissue of a patient.
 17. A convection enhanced deliverysystem comprising: (a) a first convection enhanced delivery devicecomprising (i) a flexible first support member, (ii) an elongated firstmicrocatheter carried by the first support member, the firstmicrocatheter having a length and projecting lengthwise away from thefirst support member such that a proximal end of the first microcatheteris disposed adjacent the first support member and an opposite distal endof the first microcatheter is spaced apart from the first supportmember, the first microcatheter including a first catheter lumenextending in a first direction lengthwise of the first microcatheter,and (iii) a first inlet port carried by the first support member, thefirst inlet port being in fluid communication with the firstmicrocatheter, the first inlet port being presented outwardly of andaway from the first support member in a second direction different thanthe first direction, the first inlet port being configured to engage anend portion of a first external fluid conduit such that fluid issupplied to the first inlet port by the first external fluid conduit andsuch that the first external fluid conduit projects away from the firstinlet port and from the first support member, the first inlet port beingdisposed adjacent a first external surface of the first support memberpresented outwardly of and away from the first support member; and (b) amesh support structure, the mesh support structure including crossmembers extending in transverse directions to one another so as todefine openings through the mesh support structure, the mesh supportstructure being configured and dimensioned to support the first supportmember of the first convection enhanced delivery device while permittingthe first microcatheter carried by the first support member to extendthrough at least one of the openings defined in the mesh supportstructure by the cross members.
 18. A convection enhanced deliverysystem according to claim 17, wherein the first convection enhanceddelivery device further comprises: (iv) a first fluid conduit carried bythe first support member, the first fluid conduit including a firstconduit lumen, the first conduit lumen extending in a third directiondifferent than the first direction, the first conduit lumen being influid communication with the first catheter lumen, and (v) a firstconnecting port carried by the first support member and separate fromthe first inlet port, the first connecting port being in fluidcommunication with the first fluid conduit such that fluid is deliveredby the first fluid conduit to the first connecting port, the firstconnecting port being presented outwardly of and away from the firstsupport member in a fourth direction different than the first direction,the first connecting port being configured to engage a first end portionof a second external fluid conduit such that fluid delivered to thefirst connecting port is delivered by the first connecting port to thesecond external fluid conduit and such that the second external fluidconduit projects away from the first connecting port and from the firstsupport member, the first connecting port being disposed at or outwardlybeyond a second external surface of the first support member presentedoutwardly of and away from the first support member.
 19. A convectionenhanced delivery system according to claim 17, wherein the firstconvection enhanced delivery device also comprises an attachmentmechanism configured to attach the first convection enhanced deliverydevice to the mesh support structure, the attachment mechanism includingat least one leg configured and dimensioned to directly engage at leastone cross member of the mesh support structure.
 20. A convectionenhanced delivery system according to claim 17, further comprising: (c)a second convection enhanced delivery device comprising (i) a flexiblesecond support member, (ii) an elongated second microcatheter carried bythe second support member, the second microcatheter having a length andprojecting lengthwise away from the second support member such that aproximal end of the second microcatheter is disposed adjacent the secondsupport member and an opposite distal end of the second microcatheter isspaced apart from the second support member, the second microcatheterincluding a second catheter lumen extending in a third directionlengthwise of the second microcatheter, and (iii) a second inlet portcarried by the second support member, the second inlet port being influid communication with the second microcatheter, the second inlet portbeing presented outwardly of and away from the second support member ina fourth direction different than the third direction, the second inletport being configured to engage an end portion of a second externalfluid conduit such that fluid is supplied to the second inlet port bythe second external fluid conduit and such that the second externalfluid conduit projects away from the second inlet port and from thesecond support member, the second inlet port being disposed adjacent afirst external surface of the second support member presented outwardlyof and away from the second support member, the mesh support structurebeing configured and dimensioned to support the second support member ofthe second convection enhanced delivery device while permitting thesecond microcatheter carried by the second support member to extendthrough at least one of the openings defined in the mesh supportstructure by the cross members.